From: Zac Dover Date: Tue, 1 Nov 2022 00:47:52 +0000 (+1000) Subject: doc/dev: alphabetize EC glossary X-Git-Tag: v16.2.11~202^2 X-Git-Url: http://git.apps.os.sepia.ceph.com/?a=commitdiff_plain;h=77d9c5b32d3b09da9a9a7ffa8589c688b439c904;p=ceph.git doc/dev: alphabetize EC glossary Alphabetize the glossary in doc/dev/osd_internals/erasure_coding.rst. Signed-off-by: Zac Dover (cherry picked from commit 5067f575ad6763e106164aef98f1e172042437b6) --- diff --git a/doc/dev/osd_internals/erasure_coding.rst b/doc/dev/osd_internals/erasure_coding.rst index 68eb433dc002d..c1764e8a0bb09 100644 --- a/doc/dev/osd_internals/erasure_coding.rst +++ b/doc/dev/osd_internals/erasure_coding.rst @@ -16,20 +16,6 @@ Glossary rank of the first chunk is 0, the rank of the second chunk is 1, and so on. -*stripe* - if an object is so large that encoding it requires more than one call to the - encoding function, each of these calls will create a set of chunks called a - *stripe*. - -*shard* (also called *strip*) - an ordered sequence of chunks of the same rank from the same - object. For a given placement group, each OSD contains shards of - the same rank. When dealing with objects that are encoded with a - single operation, *chunk* is sometimes used instead of *shard* - because the shard is made of a single chunk. The *chunks* in a - *shard* are ordered according to the rank of the stripe they belong - to. - *K* the number of "data *chunks*" into which an object is divided. For example, if *K* = 2, then a 10KB object is divided into two objects of 5KB each. @@ -51,6 +37,20 @@ Glossary *N*) is 9 / 12 = 0.75. In other words, 75% of the chunks contain useful information. +*shard* (also called *strip*) + an ordered sequence of chunks of the same rank from the same + object. For a given placement group, each OSD contains shards of + the same rank. When dealing with objects that are encoded with a + single operation, *chunk* is sometimes used instead of *shard* + because the shard is made of a single chunk. The *chunks* in a + *shard* are ordered according to the rank of the stripe they belong + to. + +*stripe* + if an object is so large that encoding it requires more than one call to the + encoding function, each of these calls will create a set of chunks called a + *stripe*. + The definitions are illustrated as follows (PG stands for placement group): ::